An abnormal dicentric X chromosome in a patient with short stature and gonadal dysgenesis.

A 16 year-old girl with short stature and gonadal dysgenesis was found to have a chromosomal complement consisting of 46,X,dic(X) (qter yields p22::p22 yields qter). When comparing her clinical features with 7 other cases who appeared to have precisely the same abnormal dicentric X, it was found that even though the percent of 45,X cells present varied considerably from patient to patient, these patients were remarkably similar and the stigmata, of Turner's syndrome were minimal in this group as a whole.     

Dicentric Yp chromosome in a patient with the gonadal dysgenesis and gonadoblastoma.

A patient with a short stature, gonadal dysgenesis, and bilateral gonadoblastoma had 3 cell lines in the blood and in the skin: 46,X,dic (Y) (pter vector q 1 2 : : 1 2 vector pter) as a major cell line 46,X,del(Y) (q 1 2), and 45,X. The intensively flourescent distal part of the Yq was deleted in both the Y-dicentric and Yq--chromosome. Both parents had normal karyotypes.     

X-X translocation in a patient with gonadal dysgenesis and the problem of phenotype-karyotype correlations

Summary A sex-chromatin-positive woman without stunted growth, but with primary amenorrhea, and some stigmas of pure gonadal dysgenesis had the chromosome constitution 45,X/46,Xt(X;X)(q27;q27). The abnormal chromosome formed a large Barr body and was late-labeling. The chromosome consisted of two X chromosomes attached by their long arms (end-to-end), both apparently having the partial distal deletion. Both centromeric regions showed C-staining but only one constriction. The chromosome is interpreted as an isodicentric with only one centromere functioning. Some problems of phenotype-karyotype correlations are discussed.     

Partial long arm deletion of one X chromosome in a patient with secondary amenorrhea

Summary A partial long arm deletion of one X chromosome was observed in a patient with secondary amenorrhea and with no features of Turner's syndrome. It was shown that the deleted X chromosome was the inactivated one in all metaphases of the lymphocyte culture and of the tissue culture from gonadal biopsy.The patient was detected during a cytogenetic study of secondary amenorrhea of ovarian origin.     

Partial deletion of the X chromosome in gonadal dysgenesis 46,X,del(X)(p22) identified by BUdR treatment

Summary In this report we describe a deletion of the short arm of the X chromosome in a 16-year-old female with gonadal dysgenesis.The breakpoint was localized by BUdR treatment and acridine orange staining in region 2, band 2.Of the examined cells, 3% showed an early replication of the deleted X chromosome.     

Deletion of the short arms of chromosome 20

Summary A 46, XX, del(20) (p11) karyotype (Paris Conference, 1971) was identified in an 11-month-old French-Canadian girl with a dysmorphic syndrome, multiple congenital anomalies, psychomotor and growth retardation. Both parents had normal phenotype and karyotype.     

Monosomy X and gonadal dysgenesis in a buffalo heifer (Bubalus bubalis)

Investigations on a 3-yr-old river buffalo heifer presenting anestrus revealed a chromosome make-up of 2n=49 in the lymphocyte cultures, compared with the 2n=50 characteristic of riverine buffalo. The missing chromosome was identified as one of the Xs by karyotypic analysis, and monosomy X was confirmed by C and G-banding techniques. Both ovaries of the heifer were underdeveloped, although the other components of the internal genitalia were normal. The phenotypic and karyotypic features confirmed this to be a case of ovarian dysgenesis with 49,XO karyotype similar to that of the Turner's syndrome in man and other mammals.     

De novo duplication xq22-q23 in a girl with short stature and gonadal dysgenesis

A female of 20 years of age with short stature, gonadal dysgenesis and Turner stigmata with a de novo dup Xq22-q23 was studied. The maternal cytogenetic study was normal. This case represents the smallest Xq duplication in an abnormal female. We discuss the possibility of a maternal imprinting.     

Management of males with 45,X/46,XY gonadal dysgenesis

Males with the 45,X/46,XY karyotype and malformations of the external genitalia carry an increased risk of developing germ cell neoplasia of the gonads. We have studied gonadal tissue from 10 individuals, 0.3-17 years of age, with a male phenotype and either hypospadias and/or cryptorchidism. Four patients, 0.3-15 years of age, had carcinoma in situ, 1 boy had Sertoli-cell-only pattern and the remainder prepubertal histology. Gonadoblastoma or invasive carcinoma was not found. On the basis of our current knowledge we propose a strategy for management and follow-up of these boys in order to detect possible premalignant histological changes early and prevent development of a gonadal tumour.     

XY gonadal dysgenesis in a Charolais heifer

The anatomical and cytogenetical findings on a three quarter Charolais heifer which failed to show oestrus are described. The heifer had a karyotype of 60, XY in all tissues studied and was sex chromatin negative. The vulva and vagina were normal, the cervix had a double external os, the left ovary was partially hypoplastic, there was no right gonad and a cystic dilatation of the fallopian tube was recorded.